Effect of Carbon Nanotube on properties of lightweight concrete using recycled Expanded Polystyrene (EPS)

Abstract

Expanded Polystyrene based Lightweight concrete (EPS-C) is a lightweight material with low compressive strength and high energy absorption capacity. This type of concrete is mainly applied for heat and sound insulation, towards energy saving and sustainable development. In terms of composition, EPS-C is made from a mixture of cement, mineral additives, water, chemical additives, and Expanded Polystyrene Beads (EPS) which are small hollow spherical, impermeable, and non-toxic balls. In this paper, the EPS particles were replaced with recycled polystyrene particles as aggregates for lightweight concrete. Besides, carbon nanotube (nCNT) was added to improve the properties of the concrete. The experimental results show that (i) it is possible to use recycled EPS aggregate in making lightweight concrete with a density of less than 1200 kg/m3; (ii) the combination of nCNT improved significantly the properties of lightweight concrete, i.e. reducing the water absorption, increasing compressive strength; (iii) lightweight concrete with a very low thermal conductivity, corresponding to 0.152 W/m.°C for a sample with a density of 600 kg/m3.